sql.y

这是一个开放源代码的与WINNT/WIN2K/WIN2003兼容的操作系统

                YYABORT;
            }
        }
    ;

fromtable:
    TK_FROM table
        {
            SQL_input* sql = (SQL_input*) info;
            UINT r;

            $$ = NULL;
            r = TABLE_CreateView( sql->db, $2, &$$ );
            if( r != ERROR_SUCCESS || !$$ )
                YYABORT;
        }
  | TK_FROM table TK_COMMA table
        {
            SQL_input* sql = (SQL_input*) info;
            UINT r;

            /* only support inner joins on two tables */
            r = JOIN_CreateView( sql->db, &$$, $2, $4 );
            if( r != ERROR_SUCCESS )
                YYABORT;
        }
    ;

expr:
    TK_LP expr TK_RP
        {
            $$ = $2;
            if( !$$ )
                YYABORT;
        }
  | expr TK_AND expr
        {
            $$ = EXPR_complex( info, $1, OP_AND, $3 );
            if( !$$ )
                YYABORT;
        }
  | expr TK_OR expr
        {
            $$ = EXPR_complex( info, $1, OP_OR, $3 );
            if( !$$ )
                YYABORT;
        }
  | column_val TK_EQ val
        {
            $$ = EXPR_complex( info, $1, OP_EQ, $3 );
            if( !$$ )
                YYABORT;
        }
  | column_val TK_GT val
        {
            $$ = EXPR_complex( info, $1, OP_GT, $3 );
            if( !$$ )
                YYABORT;
        }
  | column_val TK_LT val
        {
            $$ = EXPR_complex( info, $1, OP_LT, $3 );
            if( !$$ )
                YYABORT;
        }
  | column_val TK_LE val
        {
            $$ = EXPR_complex( info, $1, OP_LE, $3 );
            if( !$$ )
                YYABORT;
        }
  | column_val TK_GE val
        {
            $$ = EXPR_complex( info, $1, OP_GE, $3 );
            if( !$$ )
                YYABORT;
        }
  | column_val TK_NE val
        {
            $$ = EXPR_complex( info, $1, OP_NE, $3 );
            if( !$$ )
                YYABORT;
        }
  | column_val TK_IS TK_NULL
        {
            $$ = EXPR_unary( info, $1, OP_ISNULL );
            if( !$$ )
                YYABORT;
        }
  | column_val TK_IS TK_NOT TK_NULL
        {
            $$ = EXPR_unary( info, $1, OP_NOTNULL );
            if( !$$ )
                YYABORT;
        }
    ;

val:
    column_val
  | const_val
    ;

constlist:
    const_val
        {
            $$ = parser_alloc_column( info, NULL, NULL );
            if( !$$ )
                YYABORT;
            $$->val = $1;
        }
  | const_val TK_COMMA constlist
        {
            $$ = parser_alloc_column( info, NULL, NULL );
            if( !$$ )
                YYABORT;
            $$->val = $1;
            $$->next = $3;
        }
    ;

update_assign_list:
    column_assignment
  | column_assignment TK_COMMA update_assign_list
        {
            $$ = $1;
            $$->next = $3;
        }
    ;

column_assignment:
    column TK_EQ const_val
        {
            $$ = $1;
            $$->val = $3;
        }
    ;

const_val:
    number
        {
            $$ = EXPR_ival( info, $1 );
            if( !$$ )
                YYABORT;
        }
  | TK_MINUS number %prec TK_NEGATION
        {
            $$ = EXPR_ival( info, -$2 );
            if( !$$ )
                YYABORT;
        }
  | TK_STRING
        {
            $$ = EXPR_sval( info, &$1 );
            if( !$$ )
                YYABORT;
        }
  | TK_WILDCARD
        {
            $$ = EXPR_wildcard( info );
            if( !$$ )
                YYABORT;
        }
    ;

column_val:
    column
        {
            $$ = EXPR_column( info, $1 );
            if( !$$ )
                YYABORT;
        }
    ;

column:
    table TK_DOT id
        {
            $$ = parser_alloc_column( info, $1, $3 );
            if( !$$ )
                YYABORT;
        }
  | id
        {
            $$ = parser_alloc_column( info, NULL, $1 );
            if( !$$ )
                YYABORT;
        }
    ;

table:
    id
        {
            $$ = $1;
        }
    ;

id:
    TK_ID
        {
            $$ = SQL_getstring( info, &$1 );
            if( !$$ )
                YYABORT;
        }
    ;

number:
    TK_INTEGER
        {
            $$ = SQL_getint( info );
        }
    ;

%%

static void *parser_alloc( void *info, unsigned int sz )
{
    SQL_input* sql = (SQL_input*) info;
    struct list *mem;

    mem = msi_alloc( sizeof (struct list) + sz );
    list_add_tail( sql->mem, mem );
    return &mem[1];
}

static column_info *parser_alloc_column( void *info, LPCWSTR table, LPCWSTR column )
{
    column_info *col;

    col = parser_alloc( info, sizeof (*col) );
    if( col )
    {
        col->table = table;
        col->column = column;
        col->val = NULL;
        col->type = 0;
        col->next = NULL;
    }

    return col;
}

static int sql_lex( void *SQL_lval, SQL_input *sql )
{
    int token;
    struct sql_str * str = SQL_lval;

    do
    {
        sql->n += sql->len;
        if( ! sql->command[sql->n] )
            return 0;  /* end of input */

        /* TRACE("string : %s\n", debugstr_w(&sql->command[sql->n])); */
        sql->len = sqliteGetToken( &sql->command[sql->n], &token );
        if( sql->len==0 )
            break;
        str->data = &sql->command[sql->n];
        str->len = sql->len;
    }
    while( token == TK_SPACE );

    /* TRACE("token : %d (%s)\n", token, debugstr_wn(&sql->command[sql->n], sql->len)); */

    return token;
}

LPWSTR SQL_getstring( void *info, struct sql_str *strdata )
{
    LPCWSTR p = strdata->data;
    UINT len = strdata->len;
    LPWSTR str;

    /* if there's quotes, remove them */
    if( ( (p[0]=='`') && (p[len-1]=='`') ) ||
        ( (p[0]=='\'') && (p[len-1]=='\'') ) )
    {
        p++;
        len -= 2;
    }
    str = parser_alloc( info, (len + 1)*sizeof(WCHAR) );
    if( !str )
        return str;
    memcpy( str, p, len*sizeof(WCHAR) );
    str[len]=0;

    return str;
}

INT SQL_getint( void *info )
{
    SQL_input* sql = (SQL_input*) info;
    LPCWSTR p = &sql->command[sql->n];
    INT i, r = 0;

    for( i=0; i<sql->len; i++ )
    {
        if( '0' > p[i] || '9' < p[i] )
        {
            ERR("should only be numbers here!\n");
            break;
        }
        r = (p[i]-'0') + r*10;
    }

    return r;
}

static int sql_error( const char *str )
{
    return 0;
}

static struct expr * EXPR_wildcard( void *info )
{
    struct expr *e = parser_alloc( info, sizeof *e );
    if( e )
    {
        e->type = EXPR_WILDCARD;
    }
    return e;
}

static struct expr * EXPR_complex( void *info, struct expr *l, UINT op, struct expr *r )
{
    struct expr *e = parser_alloc( info, sizeof *e );
    if( e )
    {
        e->type = EXPR_COMPLEX;
        e->u.expr.left = l;
        e->u.expr.op = op;
        e->u.expr.right = r;
    }
    return e;
}

static struct expr * EXPR_unary( void *info, struct expr *l, UINT op )
{
    struct expr *e = parser_alloc( info, sizeof *e );
    if( e )
    {
        e->type = EXPR_UNARY;
        e->u.expr.left = l;
        e->u.expr.op = op;
        e->u.expr.right = NULL;
    }
    return e;
}

static struct expr * EXPR_column( void *info, column_info *column )
{
    struct expr *e = parser_alloc( info, sizeof *e );
    if( e )
    {
        e->type = EXPR_COLUMN;
        e->u.sval = column->column;
    }
    return e;
}

static struct expr * EXPR_ival( void *info, int val )
{
    struct expr *e = parser_alloc( info, sizeof *e );
    if( e )
    {
        e->type = EXPR_IVAL;
        e->u.ival = val;
    }
    return e;
}

static struct expr * EXPR_sval( void *info, struct sql_str *str )
{
    struct expr *e = parser_alloc( info, sizeof *e );
    if( e )
    {
        e->type = EXPR_SVAL;
        e->u.sval = SQL_getstring( info, str );
    }
    return e;
}

static BOOL SQL_MarkPrimaryKeys( column_info *cols,
                                 column_info *keys )
{
    column_info *k;
    BOOL found = TRUE;

    for( k = keys; k && found; k = k->next )
    {
        column_info *c;

        found = FALSE;
        for( c = cols; c && !found; c = c->next )
        {
             if( lstrcmpW( k->column, c->column ) )
                 continue;
             c->type |= MSITYPE_KEY;
             found = TRUE;
        }
    }

    return found;
}

UINT MSI_ParseSQL( MSIDATABASE *db, LPCWSTR command, MSIVIEW **phview,
                   struct list *mem )
{
    SQL_input sql;
    int r;

    *phview = NULL;

    sql.db = db;
    sql.command = command;
    sql.n = 0;
    sql.len = 0;
    sql.view = phview;
    sql.mem = mem;

    r = sql_parse(&sql);

    TRACE("Parse returned %d\n", r);
    if( r )
    {
        *sql.view = NULL;
        return ERROR_BAD_QUERY_SYNTAX;
    }

    return ERROR_SUCCESS;
}